A program is proposed to provide advanced training to pre-doctoral and postdoctoral fellows in the fundamentals of neuronal plasticity in the aging nervous system. The program has three key features. The first of these is Academic Bridging, whereby a principal focus will be to provide the students and fellows with concepts and research experience which address problems at the interface of basic and clinical problems in aging. This bridging will be reflected in the faculty participating in the program, the students and fellows admitted to the program, and the structure of the training program itself. Seminars and co-sponsorships by basic scientists and clinical researchers of students and fellows will assure that bridging concepts and practice will be emphasized. The second feature is Life Span Development. We believe that the aging process is part of a life span process, which should and can be investigated as part of a continuum from birth to death. Many conceptual and practical problems presently being addressed in early development are translatable to late stage aging. This translation of ideas and approaches from studies of development and adult plasticity will be a feature of the program. In general we believe that investigations of neuronal plasticity are at the very core of understanding late stage aging, since age-related decline often reflects a decrease in neuronal and functional plasticity. Thus understanding the limits and mechanisms of neuronal plasticity will clearly contribute to an understanding of aging and functional decline. In this program we will encourage the participants to address these age-related aspects of plasticity. The third key feature is that the program will be Multidisciplinary. By their very nature Neuroscience and Aging are multidisciplinary fields of investigation. The modern neuroscientist is required to understand and use methods and techniques from the full range of biological disciplines. The faculty in this program represent technical expertise in the fields of Molecular Genetics, Protein Chemistry, Cell Biology, Neurophysiology, Systems Analysis, Behavioral Pharmacology, Computational Neuroscience, and Clinical Neurology. Our goal is to train students to be able to work and think effectively in several of these areas, and this will be achieved by choosing the correct faculty, students, and fellows, and providing them a forum for discussion and interaction.